Characterization of cytokine expression in the rectal mucosa of ulcerative colitis: correlation with disease activity

Am J Gastroenterol. 1999 Sep;94(9):2441-6. doi: 10.1111/j.1572-0241.1999.01372.x.

Abstract

Objective: Mucosal inflammation in ulcerative colitis (UC) is presumed to be regulated by Th2-like cytokines. The aim of this study was to characterize local expression of various cytokines mRNA.

Methods: Total RNA was extracted from rectal biopsy specimens in 61 patients with UC, 18 inflammatory controls, and 16 noninflammatory controls. Reverse-transcription polymerase chain reaction (RT-PCR) was used to determine mRNA expression of interleukin (IL)-2, interferon (IFN)-gamma, IL-4, IL-10, IL-13, and IL-15.

Results: Expression of IL-10 was more frequent in UC (75.4%) than in noninflammatory controls (37.5%, p < 0.01). IL-4 was more frequently positive in UC (41%) than in inflammatory controls (5.6%, p < 0.01) and in noninflammatory controls (6.3%, p < 0.01). Positive expressions of IL-4 (66.7% vs 20.6%, p < 0.01) and IL-13 (63.0% vs 29.4%, p < 0.01) were higher in active UC than in inactive UC. The positive rate of IL-2, interferon (IFN)-gamma, and IL-15 expression showed no difference among the groups divided by clinical, endoscopic, and histological grade of inflammation.

Conclusions: These findings suggest that in active UC, IL-4 is pivotal, in combination with other Th2-like cytokines. In contrast, Th1-like cytokines and IL-15 bear no definite relation to local inflammation of UC.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Child
  • Colitis, Ulcerative / immunology*
  • Colitis, Ulcerative / metabolism
  • Female
  • Gene Expression Regulation
  • Humans
  • Interferon-gamma / biosynthesis*
  • Interferon-gamma / genetics
  • Interleukins / biosynthesis*
  • Interleukins / genetics
  • Intestinal Mucosa / immunology*
  • Intestinal Mucosa / metabolism
  • Male
  • Middle Aged
  • RNA, Messenger / biosynthesis
  • Rectum / immunology*
  • Rectum / metabolism
  • Severity of Illness Index

Substances

  • Interleukins
  • RNA, Messenger
  • Interferon-gamma